_flavor=postmarketos-qcom
_config="config-${_flavor}.${CARCH}"

pkgname=linux-${_flavor}

pkgver=4.17_rc3
pkgrel=4

arch="armhf"
pkgdesc="Kernel close to mainline with extra patches for Qualcomm devices"
url="https://kernel.org/"
depends=""
makedepends="dtbtool perl sed installkernel bash gmp-dev bc linux-headers elfutils-dev libressl-dev file bison flex"
options="!strip !check !tracedeps"
install=
_commit="09efb4857f1a4119eced855912043817bd96e064"
source="
	linux-${_commit}.tar.gz::https://github.com/postmarketOS/linux/archive/${_commit}.tar.gz
	config-${_flavor}.armhf
"

subpackages="$pkgname-dev"

license="GPL2"
_abi_release=$_pkgver
_carch=${CARCH}
case "$_carch" in
aarch64*) _carch="arm64" ;;
arm*) _carch="arm" ;;
ppc*) _carch="powerpc" ;;
s390*) _carch="s390" ;;
esac

HOSTCC="${CC:-gcc}"
HOSTCC="${HOSTCC#${CROSS_COMPILE}}"

builddir="$srcdir/linux-postmarketos-${_commit}"

prepare() {
	local _patch_failed=
    ls "$srcdir"
	cd "$builddir"
	# first apply patches in specified order
	for i in $source; do
		case $i in
		*.patch|*.patch::*)
			_patch=${i%::*}
			msg "Applying $_patch..."
			if ! patch -s -p1 -N -i "$srcdir"/$_patch; then
				echo $_patch >>failed
				_patch_failed=1
			fi
			;;
		esac
	done

	if ! [ -z "$_patch_failed" ]; then
		error "The following patches failed:"
		cat failed
		return 1
	fi

	mkdir -p "$srcdir"/build
	cp -v "$srcdir"/$_config "$srcdir"/build/.config
	make -C "$builddir" O="$srcdir"/build ARCH="$_carch" HOSTCC="$HOSTCC" \
		olddefconfig
}

build() {
	cd "$srcdir"/build
	unset LDFLAGS
	make ARCH="$_carch" CC="${CC:-gcc}" \
		KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-${_flavor}" \
		CFLAGS_MODULE=-fno-pic

	dtbTool -s 2048 -p scripts/dtc/ -o arch/arm/boot/dt.img arch/arm/boot/dts --version=2
}

package() {
	cd "$srcdir/build/arch/${_carch}/boot"

	if [ "$CARCH" == "aarch64" ]; then
		install -Dm644 "$srcdir/build/arch/${_carch}/boot/Image" \
			"$pkgdir/boot/vmlinuz-$_flavor"
	else
		install -Dm644 "$srcdir/build/arch/${_carch}/boot/"*zImage \
			"$pkgdir/boot/vmlinuz-$_flavor"
	fi

	install -D "$srcdir/build/include/config/kernel.release" \
		"$pkgdir/usr/share/kernel/$_flavor/kernel.release"

	install -Dm644 "$srcdir/build/arch/arm/boot/dt.img" \
		"$pkgdir/boot/dt.img"

	cd "$srcdir"/build

	local _install
	case "$CARCH" in
	aarch64*|arm*)	_install="modules_install dtbs_install" ;;
	*)		_install="modules_install" ;;
	esac

	make -j1 $_install \
		ARCH="$_carch" \
		INSTALL_MOD_PATH="$pkgdir" \
		INSTALL_DTBS_PATH="$pkgdir/usr/share/dtb"
}


dev() {
	# copy the only the parts that we really need for build 3rd party
	# kernel modules and install those as /usr/src/linux-headers,
	# simlar to what ubuntu does
	#
	# this way you dont need to install the 300-400 kernel sources to
	# build a tiny kernel module
	#
	pkgdesc="Headers and script for third party modules for postmarketos kernel"
	depends="gmp-dev bash perl"
	local dir="$subpkgdir"/usr/src/linux-headers-${_abi_release}

	# first we import config, run prepare to set up for building
	# external modules, and create the scripts
	mkdir -p "$dir"
	cp "$srcdir"/$_config "$dir"/.config
	make -j1 -C "$builddir" O="$dir" ARCH="$_carch" HOSTCC="$HOSTCC" \
		olddefconfig prepare modules_prepare scripts

	# needed for 3rd party modules
	# https://bugzilla.kernel.org/show_bug.cgi?id=11143
	case "$CARCH" in
	ppc*) (cd "$dir" && make arch/powerpc/lib/crtsavres.o);;
	esac

	# remove the stuff that points to real sources. we want 3rd party
	# modules to believe this is the soruces
	rm "$dir"/Makefile "$dir"/source

	# copy the needed stuff from real sources
	#
	# this is taken from ubuntu kernel build script
	# http://kernel.ubuntu.com/git/ubuntu/ubuntu-zesty.git/tree/debian/rules.d/3-binary-indep.mk

	cd "$builddir"
	find . -path './include/*' -prune \
		-o -path './scripts/*' -prune -o -type f \
		\( -name 'Makefile*' -o -name 'Kconfig*' -o -name 'Kbuild*' -o \
		   -name '*.sh' -o -name '*.pl' -o -name '*.lds' \) \
		-print | cpio -pdm "$dir"
	cp -a scripts include "$dir"
	find $(find arch -name include -type d -print) -type f \
		| cpio -pdm "$dir"

	install -Dm644 "$srcdir"/build/Module.symvers \
		"$dir"/Module.symvers

	mkdir -p "$subpkgdir"/lib/modules/${_abi_release}
	ln -sf /usr/src/linux-headers-${_abi_release} \
		"$subpkgdir"/lib/modules/${_abi_release}/build

	# cross-compiling: delete binaries with host arch and replace them with
	# symlinks to binaries with the target arch (packaged in kernel-scripts)
	if [ -n "$CROSS_COMPILE" ]; then
		msg "Symlinking binary scripts..."
		depends="$depends kernel-scripts"
		cd "$dir/scripts"
		local i
		for i in $(find . -type f); do
			local type="$(file -b --mime-type "$i")"
			[ "$type" != "application/x-sharedlib" ] && continue
			local native="/usr/bin/kernel-scripts/$(echo "$i" | cut -d '/' -f 2-)"
			ln -svf "$native" "$i"
		done
	fi
}
sha512sums="02fd136d24914e30decd207c3b2e0168cc9d6e4a0fc981abf8d537cd95c70583f5239d0dc7f2ae94a2ddd2ba82d822933159167801a035731a24aa1300c5ceec  linux-09efb4857f1a4119eced855912043817bd96e064.tar.gz
1961f051e2f4c3fad3fde69b08b277e3784a256115a8f30604e6b1973fd323e17ed9e5e55a3daf1a2d72770168d164ed060ff2a330d45d6cd6e3c59d4530d092  config-postmarketos-qcom.armhf"
